The whole CSAM issue is why I’d never personally run an instance, nor any other kind of server that allows users to upload content. It’s an issue I have no desire to have to deal with moderating nor the legal risks of the content even existing on a server I control.
While I’d like to hope that law enforcement would be reasonable and understand “oh, you’re just some small time host, just delete that stuff and you’re good”, my opinion on law enforcement is in the gutter. I wouldn’t trust law enforcement not to throw the book at me if someone did upload illegal content (or if I didn’t handle it correctly). Safest to let someone else deal with that risk.
And even if you can win some case in court, just having to go to court can be ludicrously expensive and risk high impact negative press.
Yeah, to be clear, MediaWiki is open source and also has alllll sorts of really cool extensions. You also already can download the entire contents of Wikipedia.
I think this desire to federate everything is going too far. Most things don’t benefit from this and in fact just become over complicated. If you can host a regular copy of a site easily… that’s frankly most of the benefits there.